Scientific Achievement
We systematically investigate the performance of carbon paper and cloth electrodes, which are of interest for redox flow batteries, as a function of compression.
Significance and Impact
Our work examines how electrode compression impacts flow cell performance. Prior studies have not included carbon papers and cloths whose microstructural features are distinct from those of felts. We study how compression impacts the electrochemical, fluid dynamic and mechanical performance of a carbon paper and a carbon cloth. We find each has specific optimal conditions and that the cloth is much less sensitive to compression than the paper. The methods described in this work are generalizable and offer insight into electrode trade-offs between mechanical robustness, permeability, and electrochemical performance.
Research Details
- Carbon paper (Freudenberg H23) and cloth (AvCarb 1071) are compressed to five different thicknesses, and their electrochemical, fluid dynamic, and mechanical performance compared.
- The surface area, permeability, and electrochemical performance of the electrodes are measured in a flow cell configuration.
- Electrode microstructures are examined with X-ray tomography and respective material elasticity explored with load cell testing.
- Polarization data is fit to a one-dimensional mass-transport model to extract transport scaling relationships across studied design space.
